Technical Field
The invention generally concerns the armoring of vehicles, in particular military land vehicles or water craft. The invention specifically concerns structural components for such a vehicle or craft, which have a layer structure with an inner honeycomb core and at least one cover layer.
State of the Art
Monolithic armor steel plates as structural elements in armored land vehicles or water craft, for example in tanks, have long been known. An armor steel plate of typically 8 mm thick armor steel is of a weight in relation to surface area of between 60 kg/m2 and 70 kg/m2. Accordingly conventional armoring results in a very high overall weight. A high armoring weight is evidently detrimental inter alia in regard to mobility, payload and also the range of the vehicle.
Armors of a modular structure, which typically include a monolithic steel plate of a thickness of 8 mm as a base armor plate and a variable additional armor plate which is geared to the respective mission, for example comprising ceramic composite tiles, are in the meantime also state of the art. In this case also the armor steel plate affords a base protection and ensures structural integrity. The variable additional armor plate (abbreviated in English as: “add-on”) makes it possible to increase the protection of the base armor plate, being adapted to the mission involved, and to adapt it for example to given effectors. Modular armors are nowadays preferred by virtue of polyvalent threats in the area of operation. However, the add-on protection of modular armors leads to an additional increase in weight of the overall system. Often vehicles or craft which are in the theater of operations are already close to or at the limit of the admissible overall mass. It will be noted however that a further advantage of modular armors is that the vehicle can be transported, divided into two freight assemblies, in particular by air, that is to say the add-on armor can be loaded and transported separately.
Accordingly there is a wish to achieve marked reductions in weight, in particular also in relation to modular protective structures.
In protective structures from areas of use of a different general kind, which do not concern protection for or armoring of vehicles or craft, it is already known to use composite or compound materials. Thus, for example, International patent application Publication No. WO 2010/033266 describes a composite panel for protection from shock waves, which is suitable for airplane construction. That composite material is intended to be suitable in particular for example for constructing baggage storage facilities within an aircraft and there to reduce the threat due to explosion, for example of a bomb smuggled on board. A further composite panel with a protective action is known from U.S. Pat. No. 7,685,921. That panel is suitable for constructing temporary quarters or storage facilities, so-called SEAHUTS. U.S. Pat. No. 5,554,816 in turn describes various portable devices for personnel protection, in which a composite panel is also used. Finally U.S. Pat. No. 3,577,836 describes protective clothing, for example a protective jacket, with a layer structure of composite materials.
The use of composite materials in a layer structure is however also already known in the field of vehicle or craft structure or armored vehicles or crafts.
International patent application publication No. WO 03/058151, for example, describes a mine protection for armored vehicles, which has a layer structure with a plurality of different honeycomb cores. That structure is complex and within the proposed layer structure also includes inter alia thin metal plates and layers of ceramic material. A good protective action is indeed to be expected from such a structural component, but with an only slight saving in weight.
European Patent Application Publication No. 0 237 095 describes a composite plate of a similar layer structure, which also has a plurality of thin metal plates and layer of ceramic material. That layer structure is intended to afford a high protective action with at the same time a limited weight in relation to surface area.
A further complex layer structure for armoring vehicles is know from U.S. Pat. No. 4,404,889. That is intended to achieve an increased protective effect, but the weight in relation to surface area is comparatively high (see Table A from U.S. Pat. No. 4,404,889) as in this case also steel plates are used within the layer structure. A further composite armor is also known from U.S. Pat. No. 4,529,640. The last-mentioned armor includes a steel plate at the enemy side, to which a honeycomb core is applied as a spacer for a layer, at the friend side, comprising glass fiber layer portions.
German Utility Model No. 88 04 278 describes an armor plate for motor vehicles, which has three layers, namely an inner layer of fiber composite plastic (FCP), an intermediate layer of ceramic material and a layer of honeycomb material, that is opposite to the vehicle plate.
European Patent Application Publication No. 1 679 484 discloses a device for fixing ballistic protective elements to objects to be protected from the effect of weapons, in particular to housings of armored vehicles.
European Patent No. 1 361 408 discloses a composite armor structure for ballistic protection of a gap between at least one armor module and the structural components of the basic structure of the vehicle or aircraft to be protected. The body of that grid-like structure has an upper, a lower and an intermediate layer with a hollow space in which a ceramic material is provided. In accordance with European Patent No. 1 361 408 the structure is fitted in addition to the structural component or components and the additional armoring, that is to say the armor modules, and it thus increases the overall weight.
French Patent Application No, 2723191 in contrast describes a layer structure which is comparatively simple in comparison with the above-mentioned examples and which manages without a layer of armor steel and which is intended to achieve an additional saving in weight. That layer structure has a core composite including a honeycomb core with cover layers on both sides, comprising fiber composite plastic (FCP). At the enemy side, glued to the core composite are ceramic tiles which are protected from external aggressions by an additional fiber-reinforced plastic layer.
The structural components described hereinbefore comprising composite material are either in the form of an actual additional armor or, when in the form of a base armor plate, they are provided with complex protective functions. None of them at all can be directly employed for a use which is preferred in recent times, as modular armor with variable additional protection.